PURPOSE: To increase the speed when many copies are taken, by stocking the image of an original, by performing exposure from the original to a photoreceptor once only, and by using the stock image for the following exposure.

CONSTITUTION: To take one copy of one original 3, image drum 18 moves away from photoreceptor 8 as shown by arrow D and an image on photoreceptor 8 is transferred to a copying form by transfer device 13. To take severed copies, image drum 18 rotates as shown by arrow E in contact with photoreceptor 8 in the 1st step, and the toner image on photoreceptor 8 is transferred to the circumferential surface of image drum 18. Next, image drum 18 moves as shown by arrow D and also rotates as shown by arrow F, and light source 20 turns on continuously to irradiate the photoreceptor with the stock image on image drum 18 via a slit, so that its image is formed on photoreceptor 8 via mirror 19, lens 6 and mirror 7.